G4NSJ – Vintage Telephones, GPO Clocks and Bells

Telephones, clocks, GPO bells and other stuff:

Alongside the radios, I have a growing museum of old telephone equipment. Most of it came from the GPO, the Post Office and BT, and much of it was made to keep the old automatic telephone exchanges running.

On these pages I describe each piece, how it worked and what I plan to do with it. Some of it is already wired up and working. Pick a heading below, or see the Site Directory for everything on the site.

Telephones

GPO 150 candlestick telephone and bell box. The classic British candlestick telephone, introduced by the GPO in 1924, and what collectors look for.
Dictograph HL-10 telephone console. An 8 key intercom made in Croydon in June 1963, just after that dreadful snowy winter. How these private systems worked. Includes a video.

GPO clocks and exchange timing

Automatic telephone exchanges needed accurate timing pulses. A master clock sent pulses to slave clocks and exchange equipment all over the building.

Gents GPO Master Clock No. 36. A one second pendulum master clock that sends pulses to slave clocks and telephone equipment. The design dates from 1925. Includes two videos.
GPO slave clocks 96A and 70A. Two electrical pulse slave clocks, to be run from my master clock, and how their hourly and daily pulses work. Includes a video.
GPO Strowger subscriber meter 160AS. A six digit meter that once counted a subscriber's calls. I might connect it to the master clock to count minutes.

Bells

Bell No. 56C. A GPO trembler bell used in telephone and signalling installations, and how its two coils should be wired.
Servant's and butler's bell box. Two flag boards from large houses, with rooms such as the library and the tradesman's door, and my plan to install one at home.

Exchanges and the telegraph

Strowger exchange and Portsdown repeater station. Jon Kay G4VFT's photos of the UAX13 and UAX12 exchanges he has preserved, and of the Portsdown repeater station before the scrap men moved in.
Vintage telegraph and telephone photos. Early GPO equipment, starting with a Victorian ABC telegraph that sent messages letter by letter before the telephone.